I have set up a pptpd server on my computer and clients can connect to it successfully. I have enabled ip_forwarding in /etc/sysctl.conf and added the following rule to my iptables to masquerade the traffic.
iptables -t nat -A POSTROUTING -s 192.168.0.0/24 -j MASQUERADE
And there is no other restricting rule in my iptables.
my pptpd ip configuration is :
localip 192.168.0.1 remoteip 192.168.0.2-254
and my local ip range is 192.168.1.0/24
the problem is my clients can not access internet via my server, is there anything else i should have done ? (both my server and clients are on the same local network)
You are doing it wrong.
Using a VPN here gives you no additional security or benefit.
Get rid of it. Simpler is always better.
If you're trying to enforce the rule that users have to be "logged in" to get out of your network, use a proxy. For example, Squid & Squidguard.